Judging from the responses so far, the consensus is this is a bad idea but I think I did not give enough background on what I am doing. The modules that are using these functions are not 'standalone' modules, they are part of the whole that is the application.
The application starts with a .pl script consisting of:
my $app = Foo::App->new();
That is all there is in the main namespace. The Foo package is responsible for loading Foo::App which in turn loads other modules necessary (which in turn load other modules necessary etc. etc.). Foo is also the package that exports the utility functions into the main namespace.
None of the modules that require the utility functions will ever be used outside of the application as they are all specific to the application. As an example, each different window in the application is a seperate module (at around 50+ right now).
The modules are meaningless without looking at the application as a whole, which is why I felt it ok to shortcut the importing of these functions. I can guarantee that the functions will be in the main namespace and they will not be messing with any other functions there (as there are none). But the problem comes when someone else comes along to maintain/extend the application. Perhaps I am being too 'clever' for my own good.
I think I may reconsider as it does only mean one extra line in each module and it will eliminate a possible source of confusion for a maintainer.
Thanks for the posts.