There are many ways to purchase cryptocurrency. A simple google search can help with this. Spreads should not be an issue for most, reputable exchanges. You do not even need to use an exchange, actually. Some options allow you to buy directly with a credit/debit card, ACH transfer, wire transfer and/or even cash. You may incur fees, depending on which route you choose, some being higher than others. Your choice will likely depend on your needs and/or what is important for you (e.g. amount of crypto needed, turnaround times, fees, customer service, anonymity, security et al.).
Here are some relevant posts…some of which may be outdated by now:
Generally speaking, the autonomous nature of cryptocurrency /does/ allow for anonymity, speedy and cost-effective transfer. However, there are many factors that contribute to the excessive fees, regulation, lack of privacy and overall, inconvenient hurdles that are currently in place for procuring and transferring it. As cryptocurrency becomes more mainstream, some of these issues may become faded memories, but that will likely take some time. Meanwhile, excessive regulation will ultimately deter progress in that regard.
As an example, you can purchase cryptocurrency via peer-to-peer transactions using sites like localbitcoins, where you may even be able to pay someone with cash. Unfortunately, however, you may pay a much higher fee for that privacy and convenience because crypto is not widely used yet, and people know that options are still, currently limited. Sites like Coinbase and others are operating a business, and like banks, they will slap you with fees for anything that they can think of.