I’m no fan of Huck, but the Club for Growth supported Pat Toomey, who voiced support for Sonia Sotomayor’s nomination and championed the repeal of DADT. They’re not exactly conservatives.
Toomey had been head of Club for Growth, IIRC, so supporting his Senate run was to be expected. Pat left the Club, in more than one way, but his apostasy wasn’t clear when he was initially running for Senate. The Club has certainly been more reliably conservative than NRC, NRCC and NRSC and has been willing to help primary RINOs. It’s not perfect, but it’s not been RINO central either.