What do you think if it's o'k when the company offers unlimited parked domains in their reseller package plans?
No subdomains.
I'm talking about sharkspace.com reselling.
Are there any limits in reality on the amount of parked domains?

Technically, disk space will be a limit as setting up a parked domain will use some.

I believe you have nothing to worry about. Anyway you do not have unlimited domain names with you

Of course, there is a limit.If you create more parked domains than your diskspace limit allows, then your account may be closed for the server resources overuse.So be cafeful when you see the unlimited number of domains in the hosting package, it is like a trick to attack new customers

There are also few drawback in terms of SEO for main domain name and the parked domain which points to the same site as the main domain.

Yes that is drawback if you get reseller account for own needs. but if you get that to resell that is ok.

Do you really require the unlimited park domains.
I think you should be choosing the package that suit to you and not being track by this type of promotion.

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He has forund whatv he has beel looking for. Some companies are readdy to offer what people what just to be found

Unlimited is a myth ther is always a limit

If you are not limited with domain names you as rule is limited with space and bandwidth and you for sure will be able to have only limited number of domain names.
That is trick not myth

A trick that is always well-planned beforehand

As any other trick actually

Well it is all over now a days. I can see several hosts selling plans saying,

(1)Unlimited Storage
(2)Unlimited Bandwidth
(3)Unlimited Email Accounts
(4)Unlimited Addon Domains
(5)Unlimited Databases
etc

This is very common. But I believe this is only to convince customer to take decision in their favor. Obviously nothing is unlimited. There are limits that even hosting company has to face. But usually those limits are not easily reachable hence it is counted as Unlimited.

I must say these are marketing tricks. They are not deceiving but trying to market their products as best as they can.

Unlimted is always is theory,there is always a limited.