My surmise is that if you asked Houston about this sort of thing, either you'd get a reply saying "we don't keep track of this," or if they did, they'd find a reason not to give an informative answer. A reasonable next question, though, would be to ask if those OCSP priests who don't offer mass on holy days of obligation take the trouble to point out that Catholics must still attend mass on those days and suggest they find a nearby diocesan parish that offers them, typically at several convenient times.
Actually, I'd say that if some of those members did go to the 12:15 All Saints' Day mass at a diocesan parish, they might discover a whole new dimension -- our parish has music at that mass, with cantors of professional-level talent. They wouldn't find this at their storefront or basement chapel. Why isn't this happening? Certianly nobody on the Anglicanorum Coetibus Society blog has mentioned it. I'm wondering if lack of seriousness is involved here somewhere, or perhaps spiritual sloth, which would be a close relative.
And a reasonable follow-up might be to ask of the lay members whether they actually do this. And here, I'm just not sure. The impression I have from the Anglicanorum Coetibus Society blog, which, let's face it, is about the only visible web presence from OCSP laity, is that it seems to be conducted by members of the smallest groups with the least options for observance -- yet they're the most publicly enthusiastic. The little Pasadena offshoot, for instance, which is the one with which Mr Coulombe is associated, is now on hiatus pending the ordination of its permanent priest.
If I were to raise this in a question-and-answer with someone from Houston, I suspect I'd get an answer along the line that "Well, we're growing. And we're growing quickly! It's true that as many as half the new groups can't offer weekday masses, or even masses on days of obligation. But they'll soon be able to!"
It would be churlish to keep insisting in such a session that I don't see this growth, that in fact the startups often just stop when the priest retires or moves on, and the groups, even if they continue with two dozen members, don't grow and don't move into better quarters.
There are various facets to Anglo-Catholicism -- most recently I've been looking at medieval romanticism, but I still keep coming back to Fr David Miller's remarks in my TEC confirmation class, that Anglo-Catholics want the prestige of calling themselves Catholic without paying the dues real Catholics have to pay. To what extent is Anglicanorum coetibus trying to appeal to a market of unserious people?