To some extent, spending is the same as dumping. When we buy goods with bitcoin, the retailer processes it through BitPay, the bitcoin is sold instantly in the exchanges, the retailer gets the fiat, not bitcoin if they choose so.

I think you are making bitcoin useful to the society. The circulation of bitcoin will make it useful and increase its value.

Some times, I think we should hold some and use some coins. Some times, I think we hold a small amount, trade and use most. Trading some coin is to make sure there is enough supply, so the coin price is not so volatile.