Well as a non resort guest (seeing as we have a home in florida that we stay in), i tend to got to the park just for a break, the number of times we have gone to a park just to have a look, or see a night show prolly outnumbers the times we have gone for the full day. We even go just for meals, nothing else.
Now the attitude that the Parks are for resort guests only is dumb, EMH are for resort guests only, not WDW resort.
Now i think Disney should keep the parks as free of Non resorts guests as possible, however if they wish to shop then they should be aloud to, after all i have paid for my park entry, my flight and my accommodation to stay in FLorida just as you may have done so to stay on property. I just choose to stay in my own home, rather than stay in a hotel 10 minutes away.
Now MK as the best solution to this, as people have stated, checks at the various land pathways. This was non resort guests who wish to shop can do so on Main Street, yet the attractions etc are still free for EMH guests.
Im sure there is a way for this to work at the other parks also, but please don't tell me that you deserve to spend more time as the resorts because you choose to stay on disney property (this is aimed at those few snobs who think they are special and clever for staying on property, not a general attack at most sensible and mature members).