You may be familiar with fine wood veneers on old wood furniture, especially many so-called antiques. You may have seen where it has chipped off or is delaminating, curling, and in general just looking terrible. That is veneer.
When they use veneer on guitars they generally cover it with a thick coat of poly that armors the top against moisture and other deteriorative elements; so I think a veneer top, so common on guitars, is not a problem. Having a real slab of thick, solid flamed wood would totally be more pleasing to me, but like Dee said, these type tops are very expensive. Some of my plain tops have solid slabs of maple on top of the mahogany.
I'll take a veneer flame top over a photo-finished flame top every time. You can have those photo-finished ones.