ACME was founded by Gustav Anvil, the inventor of the anvil, to market and deliver his now well-known invention. Anvils having a limited appeal, the initial burst of sales soon faded and ACME was not doing so well. Being practical, Gustav expanded ACME's product line and as the range of ACME products grew, so did ACME and ACME's fame.
It is a curious quirk of history that ACME seems best known in animation and cartoons, with only few mentions in live action motion pictures. There are a few theories about how this curious circumstance came to be. One claims that cartoonists liked the name as it was early in the alphabet or simply, "first in the phone book." Another holds that animators often saw ACME crates and boxes, as ACME produced a non-trivial amount of products for the motion picture industry. Yet another has Gustav's descendants, fans of animation and cartoons, sending animators and cartoonists cases of ACME ale in appreciation whenever they saw a cartoon they liked. While the first two might both be true, the third cannot be confirmed. No records of such sales or deliveries exist, as all early records were lost in a fire in 1945. By then, whatever the origin was, ACME was well established in cartoons. This, as far as can be determined, was not intentional advertising in the form of product placement. Note that if it were, ACME products would have been seen in a more positive light in many cartoons. Given the meaning of the word acme, the humor is ironic.
That does bring up the issues of quality and reliability. ACME has taken the accidental exposure in stride and rather than spend time and money on probably lengthy litigation, gone with the "as long as they spell the name right" view of the publicity. This has paid off well. ACME is now so well known for so much that some claim that ACME is an acronym, standing for "A Company Making Everything" or "American Company Making Everything." This is not the case. ACME does not make everything, at least not just yet. ACME is spelled with all capitals as that's what people recognize from labels of parcels and crates. Gustav chose the name ACME for the definition of the word acme, the highest point. Gustav would only have the best, and only produce the best, so he named the company accordingly.