Did they pay it back the next day?

I refused to borrow them any money, and I said I can't help them.

I'm not sure answering what we think is a good format for this site. Did you want to turn them down without burning bridges? Are you afraid that someone will think you are bribing them?

@thursdaysgeek Yes, I strictly do not want it to be interpreted in any way, and I'm wondering if it's an office trick. I find it also weird that they had asked me, a person whom they had known for a few days.

Have you thought about the probability that they might have forgotten their wallet at home or the atm around the corner was broke? These things can happen and borrowing a couple of bucks to a colleague so he can buy lunch shouldn't be a big deal - it's not like he's asking for a loan to finance his house..

Are 'borrow' and 'lend' now synonymous?

Which country/region is this happening in? (and origin of those involved) There will possibly be different answers depending on this.

@Tim On ELL, no. Here: why not? To OP: I'm curious. What would your solution be if you had forgotten your wallet and were hungry around lunchtime? Also, what could the trick be? At best they gain <$10 - once (coz you won't fall for the trick again), and you end up wiser about their views on other people's money.

@Tim it's a common error from speakers of some languages, when working in English, and usually clear enough form the context

@BernhardBarker if you'd seen me having missed a meal, you'd lend me the money. I'm not good company at all without sufficient food - so I normally have backup cash, but am also on good enough terms with my colleagues that I could borrow

To iain: it's written in the question ; To mcalex: If I didn't know anyone for long enough, I would abstain from asking anyone.

"Just to be clear, they didn't ask me to cover their lunch... they asked to borrow money from me" — having been in a similar situation, I've also asked for a loan of money, because it's much clearer that I'm going to pay you back if I say "Can you loan me £10, and I'll give it back to you tomorrow", than saying "can you buy my lunch & I'll get it for you next time" (what if you don't lunch together tomorrow?) Some people also have odd attitudes about giving or receiving odd small amounts of money (e.g. that it's seen as petty to remember it), so it's easier to keep it at a round figure.

It's also much easier to return $10 than it is to return $6.45 or whatever your lunch cost, if you're repaying in cash.

I agree that it is quite normal and common to borrow a small amount of money from a coworker if you forgot your wallet at home, or the cash machine was out of order, or whatever. I also agree that I don't think anyone who saw the money change hands, would be likely to think anything of it. However, usually in such a situation I would ask someone I was already friends with, not someone in the office I hardly knew.

@anotherdave also, in a typical UK situation where you might pop out for a sandwich separately, it's far simpler to borrow a tenner. If everyone goes to the canteen together and all meals cost about the same, buying one back (offering a coffee on top if necessary to ensure the borrower slightly over-returns) can be a friendly way

Also, you want to ask for money with an audience around. This way, if the person you're asking says "no", perhaps someone else can jump in and offer the money instead. It saves you from having to ask each person separately.

If you believe your co-workers can be bribed with a sum that may otherwise be considered lunch money.... well then... it may be advisable to consider another line of gainful employment.