Why you cannot buy the full version of VFP 8 instead of upgrade then?

>Here's the stupid thing that I did. I upgraded to VFP7 even if I did'nt really needed it. It was my contribution to the community.
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>I upgraded to VFP 7 but I still develop things with VFP6 because apparently I can still do that. At the moment I use VFP7 because of its intellisense but compile in VFP6. So it's the best of both worlds.
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>Now with VFP 8 it's another ball game. Upgrading to VFP8 means that development with lower versions must stop.
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>I bought some cool third party tools that allow me to build nice applications with VFP6. But with VFP7 I have some problems. So for now it's not too bad because I can still use VFP6.
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>So if I have problems with these third party tools with VFP7 I don't see why I would'nt have the same problems with VFP8.
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>But the catch is that I can't upgrade to VFP8 because I don't know if I'll have problems with those tools. And If I upgrade to VFP8 and have problems with those tools I can't go back to VFP6. Sure I could remove VFP8 (or can I from a legal point of view because at that point I upgraded to VFP8) and stay with VFP 7 or 6 or others below. But after losing some dollars doing the VFP8 test.
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>Is it only me or is there something weird with that decision by MS to do that?