I think expecting to have knowledge of running an ant or maven build  script from team of a java developer is not a big expectation.
most of the teams have at least some one who can manage to build the sources any way.

but the important question here is if they are going to stop here, or they are just backing from open source  strategy and shifting to other methods of making money.

I think they will continue to offer spring  framework open source and free. and make money on added value components.
for example currently Jasper soft is offering the jasper reports engine for free, but jasper intelligence and other higher level products are commercial.
I guess they are going to develop some commercial products on spring.