So they show up in System Profiler, but not in Disk Utility.
Post the info on one of them from System Profiler. For instance, if I attach a SanDisk Cruzer through a hub, I get something like this
USB2.0 Hub:
Product ID: 0x0608
Vendor ID: 0x05e3 (Genesys Logic, Inc.)
Version: 77.64
Speed: Up to 480 Mb/sec
Location ID: 0xfd120000 / 4
Current Available (mA): 500
Current Required (mA): 100
Cruzer Edge:
Product ID: 0x556b
Vendor ID: 0x0781 (SanDisk Corporation)
Version: 1.03
Speed: Up to 480 Mb/sec
Manufacturer: SanDisk
Location ID: 0xfd121000 / 8
Current Available (mA): 500
Current Required (mA): 200
(But delete the serial number, if any, or anything else of that kind.)