I am a bit surprised of the consensus there. I guess it depends of the scene you are in.
I am a collector and it is not rare that I buy items over weeks from the same seller. I want to maximize my order so I can combine as much as possible (paying 3$ shipping on a 5$ items does not make sense). Most sellers seem to appreciate more business (more bidder is never bad).
And from time to time I do face impatient sellers. If for any reason a seller need or even want the money faster:
- I think it is a good practice to say your time frame in your auction, 2 days is really a small time frame on eBay considering you can bid in advance, if you send an email, not everyone are in front of their computer, etc. I think if you do not mention anything, that 7 days is a minimum. After that, I would usually contact the seller to ask for extension or pay and ask him to hold my items to combine.
- Message your buyer. It is not a war, it is a buyer/customer communication. But I have saw very rude people (and not necessary because of time). Some people that sell are far from the people that say "The buyer is always right" (which I am not agreeing), but they act like they do a favor to the buyer and show a lot of disrespect.
That being said, I think it is a minority of people I dealt with that have been like that, still they sometime ruin the experience showing attitude. It does not cost much to be respectful when you initiate a conversation. I saw people go banana without any contact or what, like I had to pay for the X non-paying bidders that pissed him off or anything (I have always paid for all my transaction, except a few one that ended bad or that I was away from computer, e.g., sick, but it was not like I was not going to pay).
Now, is it OK to ask to be paid in 2 days? Yes. Sellers can set their own rules for selling. However, I think either your seller is impatient, or either it is just his regular "process" (i.e., he does that with everyone).
But the part I think you can qualify as impatient, is that he message you then re-message you 30 minutes after. No matter if it is 2 days or 14 days, if you expect someone to always be in front of a computer and answer within 30, you are nuts and cannot think further than your nose. 24 hour is reasonable, but even then it is not very long (shit happen, or people are busy). I have saw someone who did this like 5 messages over hours, and expected me to answer fast.
Oh, and not everyone have their email hooked up on their phone. If you do, fine, but do not expect everyone to have it.
Another reason I pay up multiple days after auction is that I bid on a lot of items. Dozen a days, if not hundreds if there is more interesting thing. I then process my payment when I have time, which is usually the week-end. And no, I am not always 100% aware of everything I won 10 minutes after. If I was doing this for all the ites, it will be too much time consuming. Doing them in batch when I have more free time is more efficient.
Anyway, people are calibrated differently. That is OK. But do not expect everyone to be the same as YOU. So communication is key. There is a problem, you can talk to each other. The goal of the seller should be to sell and receive the money. The buyer then want to receive his items.
Personally, most of the time I do not care if shipping take time, etc. -- as long as I get the items for my collection, I won't go coocoo. So what apply to me, also apply to others.