The left doesn't hate charters, it hates publicly subsidized private schools that are not effectively accountable. That's a subset of charters plus all vouchers.
Actual public charters, by which public schools are granted some variance of generally applicable rules to trial new methods are not a problem to the left; the hijacking of that process to create super-voucher schools when the voucher model failed to gain sufficient political support is what the left hates.
> Parents choose to send their kids there
Often, after the local regular public school has been replaced by a privately-operated charter in the same facility, and often the parents who most choose to send their children their are the ones whose most-local school was replaced, because it's the most convenient public school and going to a more distant one has added cost.