I found this paper "METHANE - PROPANE DOUBLE HYDRATE: STORAGE & TRANSPORTATION"

[link to ess.uci.edu]

It doesn't appear as easy as you've mentioned to stabilize the methane:

"Propane hydrate is being studied to develop its use as a possible storage medium for methane gas. Decomposition temperature and pressure data are measured for the propane-methane hydrates. In order to use this data for feasible purposes, time efficiency is vital. The careful balance between good thermodynamics and effectiveness results in propane hydrates formed in short periods of time (72 hours). Approximately 68% of water is successfully converted to propane hydrate SII. The propane hydrates are then charged with varying pressures of methane gas. The resulting binary hydrates (propane-methane hydrates) are stable up to temperatures of 288 K and capable of filling up to 50% of the 512 cages, confirming propane hydrate’s capacity to store methane"

Besides, the volumes and locations that we are speaking about seen rather impossible to extract and contain on short notice.