I get your point, but the previous 50MB barrier still allowed for plenty of bloat. The main ingenuity that it promoted was the ingenuity to host the rest externally to be downloaded on first application launch. This download often took more than 15 minutes (the refund period), causing tons of complaints if the application didn't work for some reason.
As the application is still restricted to 50MB, and the additional space is in the form of expansion packs, this isn't likely to result in larger code. I think it is mostly to solve the consumer complaint issue.
To be clear, the limit for the main application APK is still 50K. This change allows developers to also host on the Google Market servers up to 2 supplemental files that are up to 2Gigs in size.
Basically, this provides a better supported, more reliable, more standardized way to accommodate the already common idiom where many Android games will, immediately on first run, begin downloading the game assets (graphics, sounds, music, etc).
Sounds like a nice saying but I don't really see the need for ingenuity to setup an external data server so that the app on first use has to start downloading 2GB of data that it needs. It is not pleasant from a developer's point of view and from the user point of view. That to me seems like jumping through hoops, wasting time, money and frustrating the user