I totally agree with LondonElite - the tackiness is compounded by putting people potentially into uncomfortable situations.
As for the bribery discussion, if you are resorting to technicalities to say whether it's a bribe or not, then it's probably a good sign it is reasonably going to be seen as bribery - as reasonableness is usually the test.
It's clearly an inducement or a reward designed to advantage another person to do something improper that they would not otherwise normally do: which is to claim that you are accompanying an individual so they can circumvent a situation where they would otherwise by denied access.
There's the element of dishonesty - claiming to accompany someone for their journey when in fact no reasonable person would say that randomly begging outside a lounge is "accompanying" and the element of reward - cash is offered - that leans it beyond payment for services rendered and bribery.
That's like saying someone hanging outside an apartment or office building looking for access asking someone with a keycard to let them in, is just cardholder's guest...