Gasoline is not so friendly with silicone so we supply standard Nitrile hoses and Viton O-rings when these are used on carbed engines.
If your hoses are in good shape and you like your old style clamps, you can re-use that hardware.
For some folks, their hoses may be long in the tooth and it would be appropriate to replace all the old parts with new stuff, hence the full kit if you desire.
It doesn't seem right to offer only a half solution for everyone.
We'll delete the parts you don't want and discount the kit price if desired though.