This data is somewhat misrepresented. To be eligible for SNAP benefits, you have to also work (unless you get an exemption, like for caretaking). So the government is trying to get people off SNAP for pushing them to work, then shaming the employer for hiring people on SNAP. Walmart is a common low skill entry level job, so not a surprise that a lot of SNAP beneficiaries end up there.

The top employers that have SNAP beneficiaries also include the USPS, Amazon, Home Depot, Publix, Uber, McDonalds, Krogers...