but a 'paypal only' checkout does look amateurish (simply because anyone can do it)
Almost anybody can open up a PayPal account, since PayPal is not just a tool for ecommerce shop owner sellers, it is also a tool for the general public who are buying online.
There is a difference between the PayPal Personal accounts, the ones that the general public might have, and the PayPal Business accounts, the ones that shop owners require in order to accept credit and debit card payments direct via the PayPal site from those buyers who do not have PayPal accounts. PayPal business accounts, although they are still free, require a more stringent verification process (entering company details, business bank details, etc).
Saying that, there is still a difference between those who have PayPal business accounts which are unverified or in the process of being verified, and those that have PayPal Business verified accounts who have gone through the further verification processes in order to be able to transfer funds from PayPal to their business accounts.
So all in all, it is not as easy as you suggest for businesses to set up fully with PayPal and be able to move money into their bank, and it looks like you also have first hand experience that it is not that easy to do this too with your unfortunate first-hand experience with PayPal.
have you tried opening a bank account these days, let alone trying to get a merchant number!
The last time I had to open a new business bank was back in 1998 when my company started, so I cannot comment on this now with first hand experience. What I have noticed with some of my start-up clients though, is that their bank advisors/managers will fall over themselves in a rush to provide a new business with a merchant account, which I do find odd, since in some cases they are overkill for what a start-up needs - maybe it has something to do with the fact that the banks make a nice few hundred quick bucks when they do so. Maybe it is different for different banks, different branches, different advisors, and different company circumstances.