[A question about incidental expenses]

Hi guys,

Bio grad here. On stipend. 

Do your advisers ask you to occasionally pay for minor to moderate (often <$40, occasionally <$100) lab expenses out of pocket?

Is it ethical to do this?

I'm feeling more than a little sore about a situation like this and would like to know if I'm overreacting. The reimbursements are inevitably a giant pain in the tuchus, and in my experience the onus is on the grad student to do the footwork (and paperwork) to get recouped for doing a favor for the lab.

If I should cool my jets, that's cool, and I'd like to know.

If not, is there any way to address this, other than having a chat with the PI (which I will do soon)? I generally really really like PI, and I don't want to get PI in trouble, I just want PI to use their own damn money and start respecting mine (not to mention respecting my time).

Thanks for any feedback.