We can write off tips to handlers and helpers provided they are itemized by destination, sum, number of people tipped.
This corresponds to a wish of the passenger, and I always make sure to hand over the tip saying "The boss says thank you", so that they know where it comes from...
We usually tip baggage handlers and similar 10-20$ each depending on the country, trusted handling supervisors who make the effort to turn up for every one of our arrivals and departures get more...
Hotel staff, cleaning ladies, etc... get tipped at the crew's expense: they provide good service for MY benefit, and I consider it a mark of politeness to express my appreciation.
And no, we never get tips from anybody any more... c'est la vie...