My brother we die there, I didn't scam anybody to make my money therefore I'm not letting 1 Naira go. Doing that you're encouraging them to continue with their evil doings. Infact just because a merchant delay in paying me on purpose because I refuse to give out my number, I gave them back a taste of their own medicine.
I follow your pattern, the only amount i fit give up is the kobo, 1k no be big amount not to leave but the motive behind na another thing to look. These guys wey dey ask you to leave the money, dem no dey see am as help u dey help them instead na part of scoping. If they get those huge money to initiate P2P as vendors wetin make them go dey ask of 1k or 2k, I no see any good reason behind to leave any amount for them.
P2P merchants displaying unruly behaviours isn't a saint, they gain from accumulating what they take from peoples money, same way a banker can get punished from deducting little amount from every customers account and turn it into plus sized amount, it is nothing but stealing.