Yes, it can be normal. Some of your devices requested specifically an AAAA DNS record (which can be send and received over IPv4 and IPv6), not knowing that they might be unable to connect to the (IPv6) address returned in the AAAA record.
For my IPv4 only network i get ~20% of AAAA requests.
It is entirely expected. The IPv6 Internet has a lot of benefits and, accordingly, the Internet standards mandate to prefer IPv6 over IPv4 is both are available. When you clients don't have IPv6 connectivity, they shouldn't ask for IPv6 records. However, the vast majority of clients is not intelligent enough so they always ask for both.
I find this unusual. Are your queries dominated by internal names or by special applications which do A-only requests? On the normal "browsing", I'd almost always expect a 1:1 share between A and AAAA.