SPARQL's standard protocol for sending Queries uses HTTP[1], and yes, of course it allows clients to define the query that it sends over HTTP. HTTP QUERY would be ideal for SPARQL queries. There are also many unprotected SPARQL endpoints that you can use without any authentication [2][3].
[1]: https://www.w3.org/TR/sparql11-protocol/#query-operation
> The HTTP SEARCH method was first formally proposed in November 2008 within RFC 5323.
> Before it became a full RFC, the proposal progressed through the IETF under the working group draft name draft-ietf-httpbis-safe-method-w-body. Its formal journey began in March 2021 as an adaptation of the older SEARCH method (from WebDAV's RFC 5323), before being renamed explicitly to QUERY in later draft revisions.
There's no "pretending" this is a good idea, a ton of very smart people have spent a tremendous amount of effort refining this solution. It's incredibly well thought out.