The Beatles were only famous in Liverpool at the time, and it was a bit of agamble for this guy to actually give away amplifiers. This wasn't done. His gut feeling that this would be beneficial to Vox would prove right soon enough, but must have seemed quite foolish at the time. From that point forward until Brian Epstein's death in 1967, Vox would provide the Beatles with their latest and greatest bass and guitar amplifiers, and a keyboard or two under the agreement that whenever they performed anywhere, all amplifiers used onstage were Vox, and nothing but Vox. Posing for print ads was also part of the deal, but the Beatles got what they needed to try to be heard over the ever-increasing wail of ever-increasing, rabid, screaming fans. Demand for little-known Vox amplifiers eventually skyrocketed, as did the demands for Gretsch and Rickenbacker guitars, Hofner basses and Ludwig drums.
The Beatles didn't know that the guitars they banged around, leaned against chairs and dropped on the floor would become Holy Grails to latter-day gear geeks, nor did they really seem to give a lot of thought or concern to these tools of their trade. They were selling records and poking girls left and right, and making great noise with whatever non-pampered instrument might be lying around the studio at the time. The only Beatle that really collected or even seemed to care much about guitars was Harrison, but he gave a lot of them away to friends. I’m guessing that the Beatles probably laugh hysterically when “historians” and other gearheads seem to know and care more about what equipment was used on which track or tour than they did, which is easy because when pressed for information, they often haven’t had the foggiest recollection of such mundane details. However, that's not to say that they didn't have their cherished favorite guitars (*stay tuned).
Always free to use whatever brand of amplifiers they wished making records, a blonde piggyback Fender Bassman was reportedly used more often on more recordings from 1965 forward than any other, recording bass and guitar. They might've actually paid for that fine piece of equipment.
Some Beatle links: