Whenever my perusal of the books that contain the framework of the game we love so much generates a question, I try to look at it from all angles. While that might seem like "the most common" approach, things aren't always as they appear.
With regards to any point of contention or curiosity, we should consider that most sage advice of the authors: The First Rule (sidebar, page seven of the Core Rulebook). It reads, in part,
"If any other rule gets in the way of your fun, as long as your group agrees, you can alter or ignore it to fit your story. The true goal of Pathfinder is for everyone to enjoy themselves."
Personally, I feel that judicious application of The First Rule could resolve many of the questions that we come up with. However, as a player and GM I understand the desire to have all the tees crossed an eyes dotted, so I'll dive a little deeper with my answer.
With their once-in-a-generation genius-level intellect, eccentric behavior, and constant studies and experiments, alchemists and wizards might be viewed as kindred spirits. Commonly seen as socially inept book worms, their thirst for knowledge typically has them referencing numerous tomes, forever uncovering new ways in which to be prepared for the next adventure. Who really keeps track of all those books anyway? My point? Wizards can learn new spells through research (reading them somewhere else for the most part). When a spellbook gets full what does a wizard do? Starts a new one! As long as the wizard pays the cost (in time and coin) then they are able to learn new spells. Why not do the same thing with alchemical formulae. So long as the cost is paid, does it really matter where the formula comes from?
Additionally, alchemists tend to be intelligent, wily, and elusive. Have you ever seen a particularly buff alchemist? More books means more bulk. No matter if it's due to weight or space (or even just convenience) these types of issues usually work themselves out.
I'll finish my rambling by rounding back to my original point: In the end it is, after all, just a game. It is a known fact that an individual must be at least this tall - intellectually speaking - to play Pathfinder well. Every once in a while we need to use that power for good, and just enjoy ourselves.