Why do people charge more for visits than walks?

I agree with your thinking. When I’ve looked at sitters in my area and other areas I frequently see that the drop in visit and the walk rates are the same or if a difference exists the walk rate is higher.

Maybe instead of limiting to people who had 50 reviews, consider focusing on number of Repeat Clients (Repeat business is a better indicator of satisfied clients & clients who write reviews often do so repeatedly so that 50 could be 10 people, and Not all clients write reviews) I also recommend using the filters and zoom map when you search to generate a manageable number of sitter profiles.

A lot of sitters dislike changing cat litter therefore they charge more money for a visit than a dog walk. Some people prefer walking dogs and their walking rate is lower. It's just a personal preference. You'd have to ask them directly, no one here can tell you why other sitters do things differently.

I personally charge a little more for a drop-in because I would rather go for a 30 min walk. I like getting the exercise! With some clients pets it can be messy, more work, or I am sitting idly while their pup lays around for 20 minutes. I of course try to engage the animals, but not all want to play or run around. It's really just personal preference. Plus, a walk is more stimulating and all-around better experience for the dog, so if my rate is lower I hope more owners will opt for a walk. Sometimes I use my drop-in time to do a short walk, if time allows and the owner is comfortable with it.