Unlike on the continent or in modern times, monasteries were more multidimensional. They had to adapt to the Celtic culture and the de-Romanization of Europe.
Monasteries were still considered a more extreme way to being closer to God. For that reason, the portions of alcohol and meat a monk was allowed to have during the course of a day was spelled out in the basic laws, or rules, of each monastery. Some, following David and Uinniau of Moville, kept to a diet of strictly water and bread except under unusual circumstances, whereas the rules of most were more relaxed.
Food was not the only aspect of the Rule. The amount of time spent growing crops, the tools allowed in working the ground, and the amount of outside help (slaves or freeman) that a monastery accepted were all laid out.
Monasteries were also a means of screening the monks from the outside world. This was not always possible, however, as the medieval Celtic monastery was a teaching establishment. Hermits were fairly common as a more isolationist approach to monasticism.
As Roman government and secular Roman teachers disappeared in Britain, monasteries began to take up the slack. They welcomed the exceptionally intelligent from the lower classes as potential ecclesiastics and accepted princes from royal families and the wealthy as a means of balancing costs and helping the monastery.
Depending on the Rule of the monastery, a monk might be expected to spend a good portion of his time copying the manuscripts of passed thinkers. For a monk this could be a means of expanding the monastery library, but it was also a way for the monk to learn. Requesting a specific manuscript from another monastery invited learning and discussion. It also led to the preservation of many manuscripts that would otherwise have been lost during the Middle Ages. Of course this also meant that reads that interested monks had a better chance of survival than those that did not. Olympiodorus' histories contain many valuable insights into the ancient world that are gone forever, whereas Geoffrey of Monmouth's fanciful history of Britain has more extant copies than any other medieval work outside of the Bible.