Looks like you are in LA so it probably won't help.
If your problem is weak signals with no static or other interference, then sometimes a good booster will help. For $7.95, the "good" part is iffy.
If you are in a metro area and have interference and static, a booster will give you louder static and interference and cause even more cross channel interference.
Still, for $7.95, you don't have much to loose. If it will pass signals without reducing them when it's switched off, then you could just switch it on when you are out in the boonies and it might help a bit there.
They don't offer much info in the eBay auction, like dB gain...
An amplifier can overload a radio's AGC circuit on a strong signal too which will lead to a "poor reception" symptom.
A TV antenna amp won't improve the signal quality at the antenna head, but it will keep what signal you do get from getting attenuated in the coax leading to the TV (often 50-100')
A car only has a few feet of coax going to the radio so it wouldn't require much gain to overcome the loss..... and radio isn't as high frequency as UHF TV so the loss is less.
No, not for car audio.
But I've researched and bought some TV signal boosters. What I found there, is the most important spec is the signal to noise ratio. If the first transistor in the amplifier is cheap, it will introduce too much noise. Regardless of how much the good signal is amplified after that, reception is poor because it is overwhelmed by the noise. From what I've read, many cheap amplifiers are counterproductive because of the amount of noise they introduce.