That is true but Lipo batteries can stand 20,000 charging cycles (info gleaned online here: http://www.rc-oval.com/lipobatteries.html )
Maybe optimistic but even 1,000 flights would actually make that $172 battery much cheaper than than the equivalent amount of glow fuel.
10 gallons would be close to that price and with throttle management you will get what 200 maybe 250 flights?
It is true Lipo batteries are expensive and a gamble too. Misshandle the pack or crash the plane and that pack may be damaged.
Most packs however will last a good long time, like buying your fuel up front.