I work in what is essentially a cafe and it's great although can be hard work. .
We mainly get regulars in who are never rude to me and always like a chat.
I do 6 hour days and definitely don't do 50,000 steps, more like 12,000 unless it's a particularly manic shift. I can't get to 50,000 doing a 4 mile walk, a 6 hour shift and running a half marathon all in the same day (not far off though!)
Get some good trainers and you will be fine, your feet will throb for a while if you aren't used to being on your feet for hours but they get used to it.
We are not understaffed, some days might be busier than expected but then the following day could be dead despite the previous week being steady. So whilst we might have the odd day where we are understaffed we just get on with it because it's nobody's fault, it's just one of those things, same with staff sickness.
I've always worked front of house though ever since I was 15. I keep thinking about changing jobs for a "proper one" but it's so flexible around the kids and it's a 5 minute walk away from my house so until I get both kids in high school it's a no brainer to stay put especially because I enjoy the job.