I don't think it's just you, but you can fix this. The switch clusters are held in place by two little plastic pins that fit into holes in the handle bar, this keeps them from turning on the bar. I think that these are placed such that you can't put the bars into a comfortable position and not have the clusters hit the tank. There are two options to get them where you need them to be:
1) Get the bars where you want them then disassemble one switch cluster. Figure out how much you want to rotate it until it's both comfortable to use and doesn't hit the tank. Mark the bars and drill a new hole for the pin. Remount the cluster and repeat for the other side.
Option 1 is trickier than it seems to get the placement just right. So there's option 2:
2) Get the bars where you want them to be. Open the cluster and cut the plastic pin off. Put a wrap or two of electrical tape around the bar near the inside edge of the cluster placement and remount the now pinless cluster where you want it. The tape should provide enough friction to hold the cluster in place.
OPTION 2 IS POTENTIALLY DANGEROUS! That little pin not only keeps the cluster from turning, it keeps it from sliding off the end of the bar. Not too big a concern on the left but something to be considered on the right where the entire throttle tube and hand grip could slide off the end of the bar. The stock bar ends on the new C5 would keep the throttle from sliding off the bar but the throttle could still wedge against it and get jammed. Either way it's bad news.
That said, my bike came with both the pins already sheared off, probably poor packing or assembly at the factory. I positioned them with some tape and have had no problems so far but I do keep an eye on it. Most people go for option 2 when they get a new set or bars rather than try to drill the hole in just the right spot. I've always drilled but I can understand why most people don't. There's not much space to get the lever, cables, wires, and switch cluster all to a usable position and not hitting the tank. Getting the hole drilled just a few degrees off can screw it all up.
Also, maybe these bars just don't work for you. Any decent moto shop should have a selection of bars for about $20-25. Buy one, mount it and see if it feels good. Can you mount the controls with enough slack in the cables and without dinging the tank? Go for it!
Scott