I work in hospitality, have done for a while, also in care and retail.
I have just had my share of our 3 monthly tips, and had a day out with dd with it, and a good one, and it was massively appreciated. We still would have had the day out, but the extra money swelled the coffers so we had a better time - and in a place we ate, left a tip for good service.
I'm a night porter and As someone who works partly behind the scenes in a hotel, I don't get tips directly, very rarely anyway, although I am quite often the one that deals with odd situations, drunk and obnoxious guests and work across every department. As a team we pool all tips and they're divided up by management and everyone except the top level managers get a share.
I get paid above NMW for my role, not much but it reflects the responsibilities I have. I appreciate the tips every time they get given out, but a little while ago I really did go that extra mile for a guest. I didn't get a tip, or even a gift, I got a thank you card, and the guest had remembered my name. That meant much more than if they'd left £100. I don't expect tips, and I resent the attitude from some people that I do, and that I'll somehow be awful or give them crap service if they return because they don't tip. Everyone gets the level of service I can give, and if the opportunity presents itself, I'll go above and beyond. Sometimes because there are only 2 people to deal with, the service will seem better, if I've got 22 the service may not seem as good, that's just circumstances, but I try with each person to give them everything I can.
When I have waited on, being treated with a little respect by guests was higher on my list than someone who has been awful to me but left a large tip.
I never would assume someone was tight for not tipping, rather I assume that they could be on a tight budget and this meal/drinks/stay is a big treat. That's if I think about it at all.