If you have bunions, then you know there is a problem with finding footwear that is comfortable to wear. They need to be wide enough to accommodate the bunion or they will be uncomfortable.
One option is to use the flip flops (they call them thongs in Australia and jandals in New Zealand). There is not going to be a problem with them pushing on the bunion to be painful. Some of the brands such as the Archies from Australia and the OOFOS brand from the USA have an arch support built into them which can make them particularly comfortable and useful. They can be useful to those who need to wear foot orthotics and can not wear the open type of footwear like the flip flops.
One thing you notice in those that have bunions is that they need to be inventive and creative in what footwear that they use to make sure their feet are comfortable.