I provide services in people's homes, and for the most part I am not offered and do not expect anything. I work in the city, and sometimes if it's ridiculously hot and I've walked a couple blocks from the nearest parking space, I've had people say "Oh, it's so hot, would you like a glass of water?", and I had one kid who preferred to work at a table in his backyard, and when it was hot his mom would bring us both water, but I wouldn't expect anything more than that.
I did have one parent who, on the first day, showed me where the bathroom was and asked me to please wash my hands each time I came. I loved that, partially because it kept the child safe, but also because it gave me a gracious way to use their restroom when I was running between clients.
ETA: The work I do in people's homes is a side job, and I'm self employed so there are no "rules" for me about accepting stuff. EI may have rules, I don't know.
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