My guess is that they meant to say you can park vehicles there but you can’t convert the space to something else aside from a storage space. Eg. you can’t put walls around it and rent it out as accommodation to students or make it your craft studio.
Plain english would have sounded not legal enough for the bush lawyer drafting it so the intent ended up unclear. What, for example is a “garage purpose”? Is rehearsal space for my garage band acceptable? Lots of people have a workshop with power tools in their garage. Is that a garage purpose?
The rules where I live say: “…shall not use the … carport … for any purpose other than the parking and garaging of vehicles, the storage of … personal effects, and any other purposes from time to time approved in writing by the Owners Corporation. When storing any items other than motor vehicles in the … parking areas, members must [various points on safe storage]. Storage of larger quantities of personal effects for extended periods can become an eyesore and the Owners Corporation may require the removal of items deemed excessive …”
I think that is a lot clearer while flexible. It just needs sensible application.