Jesus the amount of rubbish I've read on this thread!
OP YANBU - weekday evenings are busy at the best of times, they're not times that anyone should be "popping in" unless they are willing to fit into your schedule, especially if they are the kind of people who need "hosting" which involves stopping whatever you're doing to give them your full attention. If they can't (or won't) fit into your schedule then they either need to forego a weekday visit or take the risk that they won't get the level of hosting that they expect.
"Appreciate them now, you'll miss them when they're dead!"
I love my parents dearly, and love that they want to spend time with my DD, but they are also the kind of people who call before they show up, and on the rare occasion they haven't they are happy to fit in to whatever plan I have for the evening - whether that means they muck in with the chores or just sit with DD while I get on ... because they accept that I don't have to drop everything just because they have turned up.
My ex's parents on the other hand are like the OP's parents, if they "popped in" then they expected to be hosted - there would be no pitching in with chores, and we basically had to drop everything to sit and have awkward chitchat over a cup of tea while I was mentally trying to work out when I could squeeze all the chores/stuff I had planned for that evening into the rest of the week's schedule without burning out, and they sat there judging the fact that the place wasn't a show home without realising that their insistence on being hosted was contributing to that
"Hire a cleaner and spend time with your kids!"
Since when was it decreed that I had to hire someone because all of my non-work time should be spent with the children? I love doing things with my DD but that doesn't mean I'm going to spend my hard earned cash to hire someone to do the cleaning I have more than enough time to do, provided my daughter can entertain herself for an hour in the evening and people don't just drop in and throw off my evening plans
"Why are you doing washing/bed changes during the week anyway?!"
I wasn't aware there was a decree that you couldn't do housework when it works best for you and was restricted to weekend days only? I work at weekends, and get random days off during the week so I do housework as it needs doing rather than on a specific day ... as long as stuff gets done routinely, what does it matter what day it is done on, provided it fits within your own schedule?
"Why are you cleaning the bathroom after work anyway?"
When should I clean the bathroom then? If it's dirty, it gets cleaned ... should I leave the toothpaste marks in the sink and water marks on the shower door until Saturday just because that's my next day off and do it then, or should I take ten minutes on Tuesday to squirt some bleach down the loo, wipe round the sink and squeege the shower door whilst I wait for the washing to finish and dinner is in the oven?
"Working full time isn't an excuse to be a bitch"
No but it is an excuse to not put your evening plans on hold because someone decided to drop by ... working full time means that I have to make full use of the time when I'm not at work to keep everything ticking over. If my parents were to drop in and expect to be hosted, I'd spend the whole "visit" thinking about how to rearrange my schedule to fit everything in, or my chance of a relax after DD is in bed is gone as I have to spend the rest of the evening catching up.
"I'd have considered it a welcome opportunity to get the kids to put their Ipads down and have some human interaction"
They're getting human interaction, just not at the precise moment of the visit because the OP was busy and they were having some down time, since when was that a bad thing?
My DD gets human interaction all day, every day ... if her using a tablet/watching tv/playing on a games console for an hour after school on a weekday evening meant I could get her tea made, a round of washing done, and a few other bits and bobs done round the house so that we could spend the entire evening after tea together, then why would I stop her?
There is a huge difference between "DCs spend all evening with technology and DCs spend time on tech while I get housework done so we can all interact together later in the evening"
"It's such a horrible feeling for your child to view your visit to them as a complete inconvenience."
I love my parents but that doesn't mean things they do are never inconvenient for me. Just like if they were to "drop in" at 8;30am when I'm trying to get out to work and get my DD out to school with everything she needs that day, that would be just as inconvenient. It doesn't mean I never want to see them, I just don't want to see them at that speciic moment.
It's a weekday evening, even without housework that I may or may not be doing, that is a busy time - DD has various extra curriculars, we might have had a play date or I might have arranged for my friends to come over, then theres the usual dinner/homework/relaxing time/bath/bedtime etcetc to fit in to a very short time ... which is why my parents know not to just "drop by" on a weekday evening. If there is an arranged visit, or even that they call first and ask if I'd be free for them to come over for half an hour, fine, I can factor that in to my schedule and arrange accordingly.