Ask HGS about it. Theres another LGS with similar policy but they are leniant about it. Could also be that I have spent a buttload of money there too. 
Paying for storage isn't unique to HGS, but you should talk to them about your specific circumstances. They are not charging for the first 2 months to allow you to get your permit. If you have an appointment that's further out than that, show them a screenshot of your appointment confirmation. As long as they see you aren't leaving the gun indefinitely, you have a good chance of talking them into waiving storage fees until the day you get your permit.
If you don't have a permit appointment, and you are trying to get that gun while it's on sale, you need to weigh the discounted price against any storage fees you might be charged. You could be saving money by getting the permit appointment first and THEN shop for/buy the gun so you avoid any fees.
Sometimes I wish they all did lay-away, so I can buy it at the promotional sale price for a % down payment, and then pay the balance in equal installments over a few months. That would help my cash flow situation as well as provide time for the permit appointment to roll around.

It costs stores money to provide secure storage space, including insurance and labor for record keeping.
These guys are in business to make money. If they provide storage, expecting to be compensated is reasonable.
OGC instituted a fixed storage fee of $32 per month if your firearm isn't picked up within 90 days. It's under their FFL transfer instructions, so I'm unsure if it also applies to purchases from them. I know transfers often cost them more than they charge, so if they aren't making money on the sale, storage fees are reasonable.
Carter said due to the current situation, the storage fee is being waived if you're waiting on a permit appointment.
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