I dont know if I would agree with that statement 
completely... While it is true cel dealers may 
buy a cel online for their own collection - and 
then perhaps later decide to sell it (again, 
online), the majority of true dealers' shop cels 
are the result of actually traveling to (or 
within) Japan... And let me tell you, a cel 
buying trip to Japan is NOT easy or cheap. 
Scouring an entire country looking for decent 
quality cels has become more and more difficult 
over recent years. Add in the numerous expenses 
(airfare, hotel, transportation) etc and its a 
real headache. Cel dealers that do this are 
providing a service, in addition to supplying 
their customers with a piece of artwork, and 
thats why you pay the price you do... I cannot 
say specifically whether or not the ebay dealer 
in question goes through this process; but I 
would caution you NOT to assume that ALL dealers 
simply "buy online, sell online". A lot of us 
still do things the old fashioned, time 
consuming and EXPENSIVE way.