Even as a kid I was confused. Where else is the money going to come from?
There are circumstances where much of the burden of increased production costs is borne by the producer. When demand is very elastic (consumers are price sensitive, or there are many good substitutes), and supply is inelastic (its hard to change the level of output), the suppliers will eat the cost.
Out of that price: $3 goes to production cost, $3 goes to tariffs, and $4 goes to profits.
Now the taxes/tariffs are doubled. The producer can up their price to $13, meaning $3 to production, $6 to tariffs and $4 to profit.
But customers might not accept any price higher than $10. They won't buy.
So instead you continue selling for $10 and your costs are: $3 for production, $6 for tariffs and $1 in profit.
That's what people mean when they say that companies are paying the tariffs. They're not profiting as much as before.
In practice it's usually a mix of higher consumer prices, lower company profits, or even some products not being imported anymore.
Which would be a nice balance to the way productivity has rocketed since the late 70s, and has mostly flowed to the top 1%.
Ultimately - and predictably - wealth hoarding becomes economic self-harm. You need distributed prosperity if you want diverse growth and economic and social stability.