Expense claims

Do people feel guilty claiming for expenses at a professional services firm?

Is it right for a lawyer to claim $150 for having lunch with a secretary of the legal counsel of a client, treating that as a client marketing expense. Is it right for a boss to claim $7 for having coffe with me, telling me that he will pay for my coffee, but in the end claiming it from the firm as a staff expense?

In desperation I claimed the following expenses today successfully. If other people weren't claiming everything, I would have paid for these expenses myself. But I felt so guilty after I claimed them, as I don't feel right in doing so. The expenses I claimed include:

1. Half of my airfare to HK - claimed to internal marketing, since the last time I went to HK for my friend's wedding, I actually did a presentation at our HK office.

2. Coffee with client - I knew this person before I realised that he is also a client of the firms. I had coffee with him the other day, and I kept the receipt. I claimed this as a client expense.

3. Bottle of wine with collegues - We went to a drinks night organised by the firm, and we stayed back afterwards when everyone was gone. Since all our bosses have left, they weren't there to pay for the extra drinks, so I paid for a bottle of wine for me and my collegues. I claimed this as a staff enterntainment expense.

Maybe I should just do my own thing and ignore how other people are exploiting the firm.