Seems very odd that some people expect to be tipped by the customer for doing their job.
If they are under paid, they should be asking the boss for a raise. If they don't get the raise they need, quit.
Open their own business, get a different job, something.
People are already paying an outrageous amount of money for a guided trip, surely the pay already is good, or can be made to be good.
If someone was to try and tip me, I would give it back.
It has become outrageous how many people think they deserve a tip for doing their job. Chamber maids, baristas, servers, bar tenders, car wash attendants, store clerks, delivery drivers, and so many more. No, it has gone too far, enough with the tipping.
If a Doctor literally saves your life, then maybe, otherwise no.