I have this Veo Stingray webcam that shows the following in
/proc/bus/usb/devices:

T: Bus=01 Lev=01 Prnt=01 Port=01 Cnt=01 Dev#= 3 Spd=12 MxCh= 0
D: Ver= 1.01 Cls=ff(vend.) Sub=ff Prot=ff MxPS= 8 #Cfgs= 1
P: Vendor=0545 ProdID=808b Rev= 3.0c
S: Product=USB IMAGING DEVICE
C:* #Ifs= 1 Cfg#= 1 Atr=80 MxPwr=500mA
I: If#= 0 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=81(I) Atr=01(Isoc) MxPS= 0 Ivl=1ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 8 Ivl=0ms
I: If#= 0 Alt= 1 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=ff Driver=(none)
E: Ad=81(I) Atr=01(Isoc) MxPS=1022 Ivl=1ms
E: Ad=82(I) Atr=02(Bulk) MxPS= 64 Ivl=0ms

Looking at the dump, this device lists as having only one interface [C:* #Ifs = 1] and yet the dump shows two interfaces [I: If#0] zeroes. Note the first If#0 has Alt=0, whereas the second If#0 has Alt=1.

I'm not a usb expert, but this seems odd. It may explain why I am having driver problems with it.

Well I can answer my own question now, no it is not screwy.

It does have one interface and two alternates on that interface. The problem I was having is that this variant has two endpoints for each alternate, rather than the one I was expecting.