It's a classic case of glomming: Americans seized on glaum (a term from Scots dialect that basically means "to grab") and appropriated it as their own, changing it to glom in the process. Glom first meant "to steal" (as in the purse-snatching, robber kind of stealing), but over time that meaning got stretched, resulting in figurative uses. Today we might say, for example, that a busy professional gloms a weekend getaway. Glom also appears frequently in the phrase "glom on to," which can mean "to appropriate for one's own use" ("glom on to another's idea"); "to grab hold of" ("glom on to the last cookie"); or "to latch on to" ("glom on to an opinion" or "glom on to an influential friend").