Quality control for outsourced customer?

It may be assumed that the quality control has been outsourced to the customer.
The first scooter I got delivered had back and forth a clear eight (wheels go about 3 to 5 mm back and forth and do not run perfectly straight).
Then I sent the scooter back immediately.
Replacement Roller had the same problem. I was not sure that was normal? To reassure myself, I drove to the nearest shop, there were "Tecaro" Scooter sold (is also a Hudora but for retailers was explained to me). The stock Tecaro there was the problem with the aft or not only easily one of the two wheels. So I also sent the spare scooter back.
The ... Tecaro ... 230 ... (or similar), whom I had seen in the shop, there is also in Amazon as "HUDORA 14230 - Bold Wheel 230". I have now ordered and get the "roller problem" has this not or only very slightly, the large front wheel is, however, a slight angle, and I am also considering to return the scooter again. Property me the article but eventually retained, otherwise probably still summer is over before I get a truly perfect instrument. Why did not I put the same from the shop? Because he there costs about 99 euros and 83.99 here. I am disappointed by the quality assurance, a product of the not 100% perfect and quality defects which should not leave my opinion that Mr. Teller company building only.