Never go to any of the US-allied countries if you owe tax money to the US. The outcome wouldn't have been any different if he had visited Portugal or Germany instead of Spain. They caught the btc-e CEO in which country? Greece? They can get you anywhere unless you are in Russia/China.
The better solution is: don't get indebted to the US.
Al Capone couldn't get away, McAfee couldn't get away. You won't get away too.
Taxes are taxes. We should do our duty to pay them, even if we don't like how "unfair" the system is. What's best? To pay taxes and live "free" (as in liberty)? Or evade them and face serious consequences in the long run?
Roger Ver made a mistake by revealing his identity to the public. If he were anonymous, he'd have a higher chance of not getting arrested. Even so, I believe he should've paid his taxes to settle things once and for all with the IRS. Now he's ultimately paying the price of what he did. Expect to see other crypto players getting arrested by the US government as it expands its outreach. Perhaps, this will force the crypto industry to move somewhere else?